The present invention relates to a combination apparatus for selectively splicing the ends of fiber slivers, or entwining or interweaving fiber slivers, in conjunction with stretch-break converting machines, cut converting machines, carding, drawing, etc. The apparatus includes a splicing mechanism having one or more pairs of nozzles that are disposed on a pair of nozzle supports in such a way that the nozzles are spaced from one another and are directed in opposed directions, with the nozzles being adapted to be supplied with compressed air, and with splicing of the ends of the fiber slivers being effected by aerodynamic turbulence. The apparatus also includes an entwining or interweaving mechanism that is disposed downstream of the splicing mechanism and has a sliver funnel that has a tapering cross-sectional transport surface, with the fiber sliver, which comprises individual fibers that are oriented essentially parallel to one another, being guided through the sliver funnel.
Manmade fibers are produced as endless filaments or tows that have a high degree of uniformity. Subsequently, for further processing in a secondary spinning mill, the filaments or tows, in conformity with their intended application, are cut to the desired fiber length or are stretch-break converted or cut converted. Whereas the cut fiber material, which is present in a random orientation, must subsequently be disentangled and carded or crimped to again draw the fibers and make them parallel, as well as to manufacture the fiber sliver, during stretch-break converting the excellent parallel orientation of the fibers in the fiber slivers, and the high degree of uniformity of the tow, is maintained.
Preparatory machines in fiber yarn spinning mills have the task of supplying a continuous fiber sliver that is generally placed in canisters and is supplied to subsequent spinning machines as needed. These preparatory machines include carding machines, crimping machines, stretch-break converting machines, cut converting machines, combing machines, drawing machines, etc. Machines that are supplied with fiber slivers include, for example, flyers, finishers, rubbing finishers, roving machines, armature-type spinning machines, ring-type spinning machines, etc.
The fiber slivers manufactured from the fiber tows in stretch-break converting machines must be adequately held together in order to be transported and further processed. In many instances this holding-together is ensured by the sliver structure, fiber crimping, finishing, etc. In certain cases additional measures are undertaken, for example by concentrating the slivers, crimping the fibers, applying coatings, by the false twist process, etc., in order in this way to improve the holding-together of the fiber slivers. However, even these measures are not always sufficient to assure the required holding-together of the fiber slivers due to the nature of the untreated material and/or for technological reasons.
For example, when stretch-break converting certain untreated materials, the latter cause difficulties in the further processing of the fiber slivers that are placed in canisters. Due to inadequate holding-together of the sliver, the fiber slivers cannot be reliably withdrawn from the canisters. If the fiber sliver splits along its length, the two sliver portions experience different tensions during withdrawal from the canister. The sliver that remains in the canister is suddenly completely withdrawn after a certain period of time. Appropriate control devices then become operative, and bring about a stoppage of production. In addition, expensive waste results.
Similarly, via the cut converting process, fiber groups are produced that after being combined to form a fiber sliver assure an only inadequate holding-together of the sliver. This drawback can be eliminated only by passing through the draw frame a number of times. In particular the supplying of the fiber sliver during high production speeds causes difficulties, elimination of which required the development of expensive and complicated sliver-guiding elements.
Finally, in cotton-combing machines, the high degree of parallel orientation of the fibers due to the combing process reduces the fiber adhesion in the fiber sliver. This can result in stoppages of production in the subsequent draw frames.
Furthermore, breaking of the fiber sliver occurs during all handling processes; these breaks can be corrected by manually connecting the ends of the fiber slivers. In other cases, for example during the delivery of the fiber slivers, it is not uncommon to dispense with a connection of the fiber slivers when breakage occurs, so that the correction of the sliver break is put off until the next processing stage. The quality of manually produced sliver connections depends upon the skill and reliability of the operating personnel. In practice frequently connections are made that are too weak and break again, or connections are made that are too strong and that lead to yarn error during the course of the further processing. The necessity for a manual intervention when the sliver breaks furthermore interferes with the endeavors for further automating the production of textiles.
For this reason, an apparatus was proposed in German Offenlegungsschrift No. 32 47 687 to mechanically produce splice connections between the ends of fiber slivers. This known splicing apparatus is predominantly used on stretch-break converting machines, cut converting machines, and for drawing. With this known apparatus, the splicing of the fiber sliver ends is effected by an aerodynamic turbulence, with one or more pairs of nozzles being provided. These nozzle pairs are spaced from one another, are directed in opposed directions, and are disposed on respective nozzle supports; compressed air is supplied to the nozzles. By means of the aerodynamic turbulence, a definite, secure, and neutral-quality connection of the fiber sliver ends is obtained.
With the heretofore known splicing apparatus, it is necessary to supply compressed air at between 2.5 and 7 bar. This range is in conformity with experience, which shows that secure splice connections of fiber slivers require a relatively high compressed air pressure. Of course, such a high air pressure necessitates a high consumption of energy. Furthermore, the air pressure cannot be increased at liberty, so that the heretofore known splicing apparatus cannot be used for those applications where an extremely high air pressure is required, for example for splicing specialty fibers, such as metal fibers, where an increased splicing action is necessary.
A particular problem with the heretofore known splicing and entwining devices is that the latter cannot be integrated together in an appropriate machine because they require too much space, so that they must always be disposed separate from one another.
Proceeding from the above, it is an object of the present invention to provide a combination apparatus for selectively splicing the ends of fiber slivers, or entwining fiber slivers, with such a combination apparatus requiring only little space, with the splicing mechanism of this combination apparatus being embodied in such a way that a splice connection can be produced at low air pressure, and with the entwining mechanism of the combination apparatus being embodied in such a way that with it an improved adhesion of the fiber slivers, and a nonproblematic transport or further processing of the fiber slivers is possible.